fix: move init guard to prevent race conditions in email-templates

The initialization guard was placed after the await I18n.loadModule() call,
which could cause race conditions if Alpine calls init() multiple times
before the guard is set. This aligns with the pattern used by other pages.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/modules/messaging/static/admin/js/email-templates.js

@@ -57,12 +57,13 @@ function emailTemplatesPage() {
 
         // Lifecycle
         async init() {
-            // Load i18n translations
-            await I18n.loadModule('messaging');
-
+            // Guard against duplicate initialization
             if (window._adminEmailTemplatesInitialized) return;
             window._adminEmailTemplatesInitialized = true;
 
+            // Load i18n translations
+            await I18n.loadModule('messaging');
+
             await this.loadData();
         },